Crucial M4 Overview
Crucial’s M4 drive looks much like all other 2.5-inch solid state drives. It has a metal housing and a Crucial logo on the front. On the back there is another sticker with information about the drive and what firmware version it is running.


Like all 2.5-inch solid state drives you have your SATA data and SATA power connections on one end of the drive. You also have mounting holes on both the top and side of the drive.


To get inside the drive you simply remove 4 screws and take the top part off of the drive. You can see how easily this is done in our unboxing and overview video. Note: When you remove the screws and take the drive apart you are voiding your warranty.

When you take the drive apart the actual PCB comes out for you to take a look at both sides. Let’s start with the side with the controller on it. Crucial is using a Marvell 88S-9174-BL2D SATA 6G chip that we have seen in some other solid state drives. This chip is the new version of the 88SS9174-BJP2 chip we saw on the original C300 drive from Crucial.


Of course this drive would be using Micron flash chips. In total you have 16 chips (8 front, 8 back) which are 16GB each and are 25nm. On the back of the PCB along with the 8 memory chips is a small cache chip, again made by Micron. This 256MB cache chip is a DDR3-1333 chip with a CAS latency of 9.

